Abstract

Loss allocation in electrical power transmission system has a significant role to play in the restructuring of electricity market since generator and demands are connected to the same network. There is the need for an efficient loss allocation scheme that could fit all market structures in different locations. This paper presents the effect of real power loss allocation on the transfer bus with zero injection power.

Three approaches- the postage stamp method (PS), proportional sharing principle (PSP) or flow tracing method and the Bus-wise loss allocation (BWLA) method were compared using appropriate mathematical notations for the development of a Hybridized real power loss allocation model.

The average values of the losses with the three methods –PS, PSP and BWLA were computed to obtain the hybridized real power loss allocation model. The effect of real power loss allocation on the transfer bus with zero injection power is then established.

The results of the work show that in PSB method, a loss of 3.0751MW was allocated to bus 1 as it contributes 142.608MW to other loads with the allocation of 1.8523MW to bus 2 with the contribution of 55MW to the other loads. In BWLA method a loss of 3.1412MW was allocated to bus 1 with its contribution of power flow to the other loads as 146.908MW while allocating a loss of 1.2381MW to bus 2 with its contribution of power flow to other loads as 58MW. In the PS method, the participants with more contributions get more benefits compared to participants with lesser contributions.

Though, network is taken into consideration in PSB, customers have no reasonable benefits as compared to the BWLA method compared to the other two approaches.

The total real power loss of 25.18MW for the 30 bus system was obtained by using PS. PSP and BWLA method. All the three methods, PS, PSB and BWLA allot zero loss to the transfer bus which has zero injection power. In PSB method, negative losses ( counter-flows) occur when number of buses increases and in BWLA  method, negative losses (counter flows) never occur even though there is an increase in the number of buses.